Technical Field
Embodiments of the invention relate generally to magnetic resonance imaging. Particular embodiments relate to enhancing images obtained from magnetic resonance equipment.
Discussion of Art
Magnetic resonance images are typically produced by algorithms that presume perfect homogeneity of a constant magnetic field B0 that used to align spins of atoms within a target volume. Homogeneity of a radio frequency magnetic field B1, the field used to perturb the spins of selected atoms within the target volume, is also presumed. These algorithms rely on presumptions that, however, do not perfectly match the physics of a real magnetic resonance apparatus. In particular, these algorithms have tended to ignore, for example, inhomogeneities of intensity of the B1 magnetic field as transmitted from an RF coil.
As will be appreciated, it is generally desirable to account for variables (e.g., imperfections) that might cause imaging equipment to deviate from the presumptions underlying the algorithms used to produce images. In view of the above, it is desirable to provide apparatus and methods for correcting the intensity of MR images, using a map of B1 transmit intensity (also referred to hereafter as transmit sensitivity). Such a map can be acquired or estimated from scan data and/or system design information.